Banjo-resonator.



B. V. KERSHNER.

BMU() RESONATOR.

.AW-Lacanau m ED AUG. 30.1915.

' Patented Jim. 14, N19.

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B,` V, KERSHNEB.

BANJO RESONATOR. n PPLlcATloH FILED Aue.3o. 1915.

Patented Jan. 14, 199.

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BENJAMIN V. KERSIINER, OF CHICAGO, ILLINOIS.

BANJO-RESONATOR.

Application filed August 30, 1915.

To all whom t may concern.'

Be it known that I, BENJAMIN V. liERsH- NER, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Banjo-Resonators, of which the following is a specification.

This invention relates to new and useful improvements in stringed musical instruments, and more particularly to shell attachments for banjos.

Practice has unquestionably demonstrated that with the ordinary banjo having an open head under the vellum, the volume of sound produced thereby could not be made sufliciently great so as to clearly carry a long distance, such as in concert halls, in theaters, etc.

rlhe principal object of this invention is, therefore, to provide a shell of novel construction, which may be readily attached to the head of any banjo now in general use. and which, when so attached, will greatly increase the volume of sound emanating from said head.

Another important object is to provide such a shell with egress openings for the sound waves, adjacent the neck only of the instrument, thereby insuring clear openings during playing.

It is a further object of the invention to provide a shell attachment of the type above referred to which will not interfere with the use of harp attachments of well-known construction, or the ready adjustment and manipulation of the same.

A still further obj ect of the invention is to construct a shell for the purpose set forth with laminated sections of alternating soft and hard woods, and to line the inner face thereof with cross strips of wood veneer, thereby insuring good resonance to the instrument, and also serving to maintain the shell against possible buckling.

These and other objects will in part be obvious and will in part be hereinafter more fully disclosed.

In the drawings, which show by way of illustration one embodiment of my invention,

Figure l is a bottom plan showing my inve-ntion applied to the head of a banjo.

Fig. 2 is a longitudinal sectional view therethrough.

Fig. 3 is a transverse section through the shell only, and

Fig. 4: is an enlarged detail sectional view showing another construction of the shell.

Specification of Letters Patent.

Patented Jan. 14, 1919.

Serial No. 48,113.

Like reference numerals indicate corresponding parts in all the gures of the drawings.

Referring to the drawings, A indicates, generally, a banjo which is provided with the usual head B having a neck 5 extending therefrom. The head B includes the usual rim 6, and through this rim extends the usual dowel piece 7, said dowel piece being arranged in longitudinal alinement with said neck, and extending diametrically across the rim 6. The rim 6 supports, on'one face thereof, the usual vellum S, and supported by said vellum is a bridge piece 9, over which the strings 10 are led from the tail piece 1l to the different pegs (not shown) at ther outer end of the neck 5.

My invention comprises a concavo-convex shaped shell C, and this shell is detachably, but rigidly, secured to the edge of the banjo rim 6 opposite the vellum 8, the convex surface of said shell projecting outwardly from the drum head B. The body portion of this shell consists of alternate sections of soft and hard wood l2 and 13 respectively, the hard wood sections being much narrower than the soft wood sections. These sections are preferably arranged longitudinally of the instrumentthat is, in the same general direction as the neck 5.

rIhe body portion of this shell is substantially circular in outline so as to be positioned against the edge of the rim 6 opposite the vellum and arranged with the marginal edge substantially flush with the peripher).v of said rim. Extending radially from the inner edge of this shell is a projection li. This projection is formed by continuing several of the centrally disposed laminated sections 12 and 13 beyond the circular area of said shell, the longitudinal extension of the sections thus providing a rigid front support for the device. The marginal edge portion of said body portion of the shell is secured to the rim 6 by a plurality of suitable fastening devices X. such as screws or the like. In this instance screws have been employed, and the heads thereof are countersunk and bear against flanged bushings Y. which are embedded in the shell. One of these fastening means is shown in section in Fig. 2. From the foregoing, it will be observed that this shell is not only rigidly secured to the rim 6 of the banjo head, but is also rigidly secured to the neck 5 of said banjo.

In order to provide egress openings for the sound waves, I have formed the marginal edge portion of the shell body on opposite f smothered. Thus, with my invention, the

openings or recesses 15 are disposed at a point farthest removed from the player.

Surrounding the body portion or laminated sections is a plurality of wooden strips 16, and surrounding these strips is a `binding element 17, which, in this case, is ivory. The strips 16 and the binder 17 serve to preventthe laminated sections 12 and 13 from having any relative movement whatsoever, and they also serve to form a substantial marginal edge for the shell to bear against the rim 6 of the banjo head.

The inner face of the body por-tion of this shell is covered by strips of wood veneer. These strips extend in a direction at right angles to the length of the laminated sections 12 and .18, and assist said laminated sections in forming a rigid body for the shell. Secured to the inner face of the shell Valong the edge of each opening or recess 15 is a strip 18, which strengthens the marginal edge of the shell along said recess.

In order to reduce the volume of sound, banjos have been heretofore equipped with an attachment known to the trade as a harp attachment. One of these harp attachments is shown in Fig. 2 of the drawings, in fragmentary and part sectional fashion to show the manner of its use with the shell structure of my invention. It consists of a wooden block 19 disposed between the dowel piece 7 and the vellum 8. This block is positioned between the arms of a bracket 20, and is normally held in engagement with the vellum through the medium of a rubber band 21, or the like. A cord 22 is connected at one end to the block 19 and this cord extends through the dowel piece 7 and is connected by a take-up 23 to a cord 24. Pivotally secured to the rim 6 of the head is a hand lever 25, and this lever is connected to the other end of the cord 24. A stationary latch 26 is also secured to the rim and is adapted to be engaged by one arm of the lever 25. This lever 25 is disposed adjacent the neck 5, and within one of the openings or recesses 15 of the shell. When more volume of sound is desired, the hand lever 25 is moved to engage the latch 26, and this movement of the latch tensions the cords 22 and 24 and, consequently, the block 19 is disengaged from the vellum 8.

In the construction shown in Fig. 4, the shell consists of a plurality of sheets secured together by any adhesive, such as glue, then compressed into shape while said adhesive is drying. This shell comprises an outer sheet or layer 26 of hard wood, an inner layer 27 of soft wood, the grains of these 'layers extending in parallel relation, an inner sheet or layer 28 of soft wood secured to the layer 27, the grain thereof extending in a direction different from the grains of the layers 26 and 27, and a binding Sheet 29 of fabric disposed between the outer layer 26 4and the inner layer 28. After these layers have been compressed, these laminated sheets or layers form a homogeneous mass, the outside layer 26 of hard wood serving to maintain the shell thus formed in its curved formation.

Having thus described my invention, what I claim is:

1. A resonator for banjos, comprising a shell having its edges shaped to closely follow the free edge of the banjo rim throughout the major portion of the latter, said shell having a rentrant portion adjacent i the neck of the banjo to permit the escape of sound.

2. The combination with a banjo head and neck, of a substantially circular shell having a reen-trant contour on a portion of its periphery, said shell closely fitting the free edge of the banjo head and said rentrant contour providing for the egress of sound.

3. The combination with a banjo head and neck, of a concave shell having its marginal edge closely fitting the free edge of the rim of said head, said shell having an extension reaching onto the neck and fastened thereto and having openings` therein on opposite sides of said extension.

4. The combination with a banjo head, of a resonator shell having its edge closely iitted to the free edge of the rim of said head, and having an open space adjacent the neck of the banjo for the egress of sound.

In testimony whereof I aiiix my signature in presence of two witnesses.

BENJAMIN V. KERSHNER.

'Witnesses:

REUBEN C. PRATT, CHAs. E. VALENTINE.

Copies of this patent may be obtained for ve cents each, by addressing' the Commissioner of 2atents.

Washington, D. C. 

